10 Movies That Struggled To Define Their Own Rules
7. Who Built All The Cars? - Cars
The Cars franchise may not rank among Pixar's greatest works - quite the opposite, even - but fans have nevertheless been left curious and baffled by the world within which these stories take place.
The Cars movie are of course defined by their anthropomorphic vehicular characters, and despite there being many recognisably human aspects to the world, people themselves are nowhere to be seen.
This is never explained, nor is the means through which the cars are actually created, and despite being asked directly about it, the series' writers haven't ever provided a concrete answer.
Though Cars 3's creative director Jay Ward has posited his own theory that the cars became sentient and overthrew humanity, in turn rendering human beings extinct, that obviously isn't canon, as fun an idea as it is.
The official line is literally, "Try not to get too hung up on the surreal nuts and bolts of it," but there are nevertheless a lot of fans who would love to see an origin story for the world of Cars.